Session 7: Software & System Servicing

'My computer is slow' is not a diagnosis, and the fastest way to waste an hour is to start uninstalling things. Open Task Manager and look at the actual numbers: which process is consuming CPU, how much of the RAM is in use and whether it is saturated, and — most revealingly — whether the disk is at 100%. A disk pegged at full utilisation on a mechanical drive is the single most common cause of an unusable Windows machine, and it points straight at the SSD upgrade from session four rather than at any software fix.

Then look at startup programs. A machine that takes three minutes to become usable usually has twenty applications launching at boot, each competing for the disk. Disabling the unnecessary ones in Task Manager's Startup tab is free, reversible and routinely transforms a machine. Note what you disable so you can undo it if the customer needs something back.

Check the basics that are routinely overlooked: how full the system drive is — Windows needs meaningful free space to operate and a drive above roughly 90% full degrades badly; how much RAM is installed against what is actually needed; and whether the machine is thermal throttling, which session three and five cover and which presents identically to a software problem. Evidence first, action second, and write down what you found.

The distinction determines everything about the job, and a few tests settle it. Does the problem occur in the firmware or in a bootable environment? If a machine is unstable in Windows but stable when booted from a USB Linux stick or a diagnostic tool, the hardware is probably fine and the fault is in Windows. If it crashes in both, suspect RAM, storage or heat.

Blue screens carry a stop code, and that code is a genuine clue — `MEMORY_MANAGEMENT` points at RAM, `CRITICAL_PROCESS_DIED` and `INACCESSIBLE_BOOT_DEVICE` at storage or drivers, `WHEA_UNCORRECTABLE_ERROR` at hardware. Photograph the code, or note that Windows stores minidumps you can read later. Guessing at a blue screen's cause without the code is how a technician replaces a perfectly good part.

Does the problem follow the user or the machine? If it happens only in one person's profile, the profile is corrupted and a new one fixes it. If it happens for every user, it is system-wide. That single test — create a second local user and log into it — takes two minutes and it splits an enormous category of problems in half.

Run a scan with a reputable tool — the built-in Windows Defender is genuinely adequate for most cases, supplemented by a second-opinion scanner for anything stubborn. But understand what scanning does and does not achieve. It removes detected threats; it does not undo everything a threat did, and it cannot guarantee the system is clean afterwards, because sophisticated malware is specifically designed to persist and to hide from scanners.

This leads to the honest professional position: for a machine with a serious infection, and especially one used for banking or business, a clean reinstall is the correct answer, not a cleanup. A cleaned machine is probably fine; a reinstalled machine is known to be fine. Where the customer handles money or sensitive data, 'probably' is not good enough, and saying so is the responsible advice even though it is more work and a harder conversation.

For lighter cases — adware, a browser hijacker, a toolbar — targeted removal is reasonable: reset the browser, remove unknown extensions, uninstall unknown programs by install date, and check the scheduled tasks and startup entries where persistence hides. Then change the passwords for anything important, from a different device, because credentials captured before removal are already compromised regardless of whether the malware is gone.

The rule that governs this whole area is: if it works, do not update it out of curiosity. Driver updates are not improvements by default — they are changes, and any change can break something that was fine. Update a driver when there is a specific fault it addresses, a specific feature you need, or a known security issue. Otherwise leave it.

Get drivers from the machine or component manufacturer, not from a generic driver-updater utility. Those utilities are a common source of damage and of malware, and they frequently install the wrong version. On a laptop, the manufacturer's support page for the exact model is the source; on a desktop, the motherboard and component manufacturers. Windows Update handles most drivers adequately for everyday hardware.

Windows updates should be kept current for security, but the discipline is to update deliberately rather than mid-job. A machine that restarts during a repair loses your place and occasionally corrupts the work in progress. Pause updates while you work, complete them before handing back, and confirm afterwards that the machine boots and its devices function — because an update that breaks a network driver or a touchpad is your problem the moment you hand the machine over, not the customer's.

A clean reinstall is the most effective software repair there is and it is underused because technicians fear the data loss. The procedure removes that fear: recover the data first, to an external drive, and verify the copy before touching anything. Then back up what people forget — browser bookmarks and saved passwords, email archives, licence keys for paid software, and any application settings that took the customer years to configure. Losing a customer's licence key is a real and avoidable failure.

Then install from clean media, install drivers from the manufacturer, run Windows Update to completion, reinstall the customer's applications, restore the data, and verify. Verification matters: open a sample of the restored files and confirm they are intact, confirm the email and browser are working, and confirm the licences activated. A reinstall you have not verified is a job you will hear about again.

The routine service that keeps a machine healthy is short and worth offering as a package: clean the dust and replace the paste, check drive health through S.M.A.R.T., verify the backups are actually running, review startup programs, complete the updates, and confirm the antivirus is active. Most of these are checks rather than repairs, and a machine serviced twice a year rarely develops the dramatic failures that bring customers in panicking — which is a better outcome for them and a steadier income for you.